PUT api/v1/sms/messages/{messageID}

This method allows the user to update a message that has already been sent.
The updates that are allowed are:
1. The content of the message.
2. Add new contacts to the message.
3. Removing contacts from the message.
4. Updating the expiration date.
5. Updating the dissolve settings. Updates are allowed only if the following conditions are met:
1) The message has not expired.
2) The message has not been read by any of the recipients if updating the contents of the message.